quantum electrodynamics summary

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Below is the article summary. For the full article, see quantum electrodynamics.

quantum electrodynamics (QED), Quantum theory of the interactions of charged particles with the electromagnetic field. It describes the interactions of light with matter as well as those of charged particles with each other. Its foundations were laid by P. A. M. Dirac when he discovered an equation describing the motion and spin of electrons that incorporated both quantum mechanics and the theory of special relativity. The theory, as refined and developed in the late 1940s, rests on the idea that charged particles interact by emitting and absorbing photons. It has become a model for other quantum field theories.

Richard Feynman Summary

Richard Feynman was an American theoretical physicist who was widely regarded as the most brilliant, influential, and iconoclastic figure in his field in the post-World War II era. Feynman remade quantum electrodynamics—the theory of the interaction between light and matter—and thus altered the way

Feynman diagram Summary

Feynman diagram, a graphical method of representing the interactions of elementary particles, invented in the 1940s and ’50s by the American theoretical physicist Richard P. Feynman. Introduced during the development of the theory of quantum electrodynamics as an aid for visualizing and calculating